Installations for automated welding processes such as welding robots need a large quantity of welding wire in order to minimize changeover downtime and maximize productivity. For safety and handling reasons, in modern installations the welding wire is not placed in the immediate proximity of the welding robot, but at a safer distant place where more floor space is available and the pack handling is easier. The welding wire can be supplied in the form of a large bulk pack which can contains from few to several hundreds of kilograms of welding wire. From the bulk pack, the welding wire is delivered to the welding robot by means of a welding wire liner, also called conduit, in which the welding wire is transported with minimized friction.
The welding wire is transported from the bulk pack to the welding torch mounted on the welding robot by means of a feeding system. Usually, the feeding system comprises a driving motor and one or two couples of feeding rolls which are pushing the wire through the welding torch liner into the welding torch. The feeding system ensures that the required amount of welding wire is delivered to the welding torch where it is being melted at a welding arc in order to join two base metal parts.
Even though the feeding system advances the welding wire, they do not keep a record of the actual length of welding wire being fed nor the actual weight of welding wire being deposited over a certain period of time.